Who might waste a lot of time serving people? (7)
I believe the answer is:
waiters
'people?' is the definition.
(waiter is a kind of person)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for waiters that I've seen before include "Servers at tables" , "Garcons" , "Table servers" , "Wariest kind of attendants" .)